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Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor

G. Schmidt·L. W. Molenkamp·A. T. Filip·B. J. van Wees
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Abstract

We have calculated the spin-polarization effects of a current in a two dimensional electron gas which is contacted by two ferromagnetic metals. In the purely diffusive regime, the current may indeed be spin-polarized. However, for a typical device geometry the degree of spin-polarization of the current is limited to less than 0.1%, only. The change in device resistance for parallel and antiparallel magnetization of the contacts is up to quadratically smaller, and will thus be difficult to detect.

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G. Schmidt, L. W. Molenkamp, A. T. Filip, B. J. van Wees. 2000-07-20. Basic obstacle for electrical spin-injection from a ferromagnetic metal into a diffusive semiconductor. https://doi.org/10.1103/physrevb.62.r4790

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